A particle-containing environment simulation device

Abstract

The application discloses a kind of particle-containing environment simulation devices, which can be used to simulate particle-containing environment, and mainly includes particle delivery system, test system, recovery system and the like, which can simulate closed or open particle environment. Together with test measurement equipment, it solves the problem of accurately capturing test dynamics in actual particle-containing environment. Different delivery speeds are controlled by a speed controller, delivery rates are controlled by a flow control valve, and test height and wind angle are adjusted by a test bench, to meet the simulation requirements of particle-containing environment under more different conditions and provide test conditions for particle-related research such as dust and friction erosion. The application has low cost and is easy to transport.

Description

Technical Field

[0001] This invention belongs to the field of environmental impact reliability testing and is used to simulate the reliability test of specimens in a particulate environment under the coupled effects of multiple factors. Background Technology

[0002] Environmental simulation technology is a new emerging technology that mainly studies the artificial reproduction of various natural environments and the testing technology of products in simulated environments. With the gradual deterioration of my country's climate and environment, the impact of special environments on the quality and reliability of mechanical and electronic products is becoming increasingly prominent. It is difficult to carry out reliability and related test research in special environments containing particles such as sandstorms, dust, smoke, powder, and sand. It is impossible to quantify the impact of coupled environmental factors on product reliability testing, accuracy correction, or durability testing. There is very little technical information on particulate environment simulation devices in the published Chinese patent literature. Studies on sandstorms or powder alone are singular and complex, and some cannot be adjusted from multiple angles.

[0003] In order to study the impact of special environments on the reliability, accuracy correction or durability testing of mechanisms, traditional methods need to be improved. With the requirements of simple structure and strong applicability, a particle-containing environment simulation device that can quantify environmental coupling factors needs to be designed and developed. Summary of the Invention

[0004] The purpose of this invention is to provide a particle-containing environment simulation device, which provides a simulation test device for particle-containing environments (including but not limited to windblown sand, dust, smoke, powder, sand, etc.). This experimental device can conveniently simulate the actual particle-containing environment in the laboratory, solving the problem of accurately capturing the dynamics of actual particle-containing environments. By adjusting the wind speed and material conveying rate, it can meet the simulation requirements of more particle-containing environments, providing important scientific basis and theoretical support for research on the impact of particulate environmental factors such as dust and friction erosion on product reliability testing, accuracy correction, or durability testing.

[0005] The technical solution to achieve the purpose of this invention is as follows:

[0006] A particle-containing environment simulation device includes a centrifugal fan, a test chamber, and a test bench installed inside the test chamber;

[0007] The centrifugal fan is connected to the test chamber through a turbulent flow section; a material conveying funnel is provided on the air outlet of the centrifugal fan;

[0008] The material conveying hopper is equipped with a flow control valve to control the opening and closing of the material conveying hopper and the flow rate, and is also equipped with a flow sensor to detect the real-time flow rate and transmit the detected data to a computer.

[0009] The test bench is equipped with an attitude adjustment mechanism, which can adjust the distance between the test bench and the air outlet, as well as the windward angle of the test bench.

[0010] The test chamber is equipped with an anemometer and a concentration monitor to detect the wind speed and particle concentration inside the test chamber and transmit the detected data to a computer.

[0011] The computer is used to calculate the conveying rate based on the cross-sectional area of ​​the air outlet, the real-time detected wind speed and particle concentration, and to control the flow control valve below the conveying funnel and the speed controller of the centrifugal fan to meet the requirements of different particle concentrations and wind speed settings in different tests.

[0012] The significant advantages of this invention compared to existing technologies are:

[0013] (1) The simulation device described in this invention is applicable to various particulate-containing environments, such as wind and sand, dust, smoke, powder, and sand. (2) This invention can simulate more realistic actual particulate-containing environments and can be adapted by changing different wind speeds and particulate concentration requirements. (3) The test bench designed in this invention can be adjusted in terms of front and back, height, and windward angle. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of the particulate environment simulation device of the present invention. Figure 1 .

[0015] Figure 2 This is a schematic diagram of the overall structure of the particulate environment simulation device of the present invention. Figure 2 .

[0016] Figure 3 This is a detailed drawing of the test bench of the present invention. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0018] Combination Figure 1 This embodiment of a particle-containing environment simulation device includes a conveying system 1, a testing system 2, and a testing bench 3, with the following specific structure:

[0019] Please see Figure 2The conveying system 1 includes a centrifugal fan 5, a flow control valve 7, a material conveying hopper 9, and a turbulent flow section 10. The centrifugal fan 5 is connected to a speed controller. The material conveying hopper 9 is located at the outlet of the centrifugal fan 5, and the material conveying hopper 9 is equipped with a flow control valve 7. A flow sensor 8 is installed inside the material conveying hopper 9, and the flow sensor 8 is connected to a computer 4. The outlet 6 on the right side of the centrifugal fan 5 and the extended turbulent flow section 10 facilitate the turbulent flow of sand and dust. The turbulent flow section 10 is connected to the test chamber 11. The test chamber 11 is connected to the contracted recovery section 16, which can recover particulate matter for recycling. Scattered particulate matter is collected by the inclined surface below the environmental simulation test chamber, realizing the recycling of particulate matter.

[0020] The experimental system 2 includes an experimental chamber 11, an anemometer 15, a concentration monitor 14, and an experimental platform 13, used for conducting relevant environmental simulation experiments. The experimental chamber is composed of 5mm acrylic panels, allowing for observation and recording at any time. The upper panel of the experimental chamber 11 is detachable, while the other panels are sealed. The experimental chamber 11 is sealed to the left-side extended turbulent flow section 10 and the right-side contracted recovery section 16. A sliding groove 12 is provided at the bottom of the experimental chamber 11, and the sliding groove 12 of the experimental platform 13 is slidably engaged to adjust the distance between the experimental platform 13 and the air outlet. The anemometer 15 and the concentration monitor 14 are installed inside the experimental chamber 11 to detect the wind speed and particle concentration, respectively. Both the anemometer 15 and the concentration monitor 14 transmit the detected data to a computer. Based on the calculated particle concentration, the computer controls the opening of the flow control valve to control the material conveying rate and controls the speed controller of the centrifugal fan 5 to control the wind speed.

[0021] Combination Figure 3 The test bench 13 includes a test bench surface 13-2, a lead screw 13-3, a rotating handwheel 13-4, a wing nut 13-5, a middle plate 13-6, a scissor-type linear array deployable structure (telescopic frame) 13-7, bolts 13-8, and a test bench base 13-9. The test bench 13 is placed at the bottom of the test chamber. The test bench base can move left and right and is fixed by bolts. The test bench 13 is adjustable in angle and height. Figure 2The diagram shows a detailed view of the test bench 13 of the present invention. The middle plate 13-6 of the test bench 13 is hinged to the left support plate of the test bench base 13-9 via a pivot 13-1. The middle plate 13-6 has through holes at its four corners, with nuts welded to its inner side. The nuts are perpendicular to the side of the middle plate 13-6 with the holes. A lead screw 13-3 is installed at the four through holes of the middle plate 13-6 and the test bench surface 13-2 and engages with the nuts. A handwheel 13-4 is provided on the lead screw 13-3, allowing for height adjustment of the test bench surface 13-2 by rotating the handwheel 13-4. To ensure stability, a butterfly nut 13-5 is added for fixation after adjustment. A scissor-type linear array deployable structure 13-7 is provided between the right side of the middle plate 13-6 and the test bench 13-9. The scissor-type linear array deployable structure 13-7 can be adjusted up and down by turning the bolt 13-8. Combined with the pivot 13-1, this allows for angle adjustment of the middle plate 13-6 and the test bench surface 13-2.

[0022] When this invention is in operation, firstly rotate the lead screw 13-3 controlling the test platform to adjust the test platform 13-2 to the required height according to the test requirements. Then, turn the four bolts 13-3 through the handwheel 13-4 to adjust the height of the test platform, and then fix it with the wing nut 13-5. Adjust the windward angle of the test platform 13-2 by turning the adjusting bolt 13-8 of the scissor linear array deployable structure 13-7.

[0023] To convert the actual particulate-containing environment into indoor environmental variables, relevant physical quantities of the particulate-containing environment are used for conversion. The conversion between feed rate and particulate concentration is related to the feed rate M. S This is related to physical quantities such as the cross-sectional area of ​​the air outlet A, the wind speed V, and the particle concentration Q. It can be expressed using a dimensional expression, where the dimension refers to the category of the physical quantity, and can be represented by dim:

[0024] dimQ=(dimV) α (dimM S ) β (dim A) γ #(1)

[0025] Where α, β, and γ are undetermined constants, and

[0026] dimQ = ML -3 dimV = LT -1 dimM S =MT -1 dim A = L 2 #(2)

[0027] Substituting equation (2) into equation (1) yields...

[0028] ML -3 =(LT -1 )α (MT -1 ) β (L 2 ) γ =M β L 2γ+α T -α-β #(3)

[0029] Where the basic dimensions M, L, and T are the dimensions of mass, length, and time, respectively. Because dimensional analysis requires ensuring homogeneity of dimensions, we can obtain:

[0030] α=1, 2β+γ=-3, -α-β=0#(4)

[0031] so

[0032] α=1, β=-1, γ=-1#(5)

[0033] so

[0034] dimQ=(dimV) -1 (dimM S ) 1 (dim A) -1 #(6)

[0035] Right now

[0036]

[0037] Finally, the material feeding rate M can be obtained. S The formula for converting between particle concentration Q and flow rate, based on the definition of flow rate in fluid mechanics, allows for the setting of the conveying rate.

[0038] Right now

[0039]

[0040] The simulation device can meet the particle concentration Q requirements of different tests according to the feeding rate.

[0041] The particulate matter concentration of the particulate environment to be simulated is calculated by formula (8), and the required conveying rate is calculated. The conveying rate of the flow control valve 7 is controlled by the flow sensor 8. The particulate matter is placed in the conveying funnel 9, and the required conveying rate is adjusted by the flow control valve 7. The required wind speed is adjusted by the speed controller 4. The particulate matter is mixed in the turbulent section under the action of the wind speed and enters the environmental simulation test chamber 11. The conveying rate is adjusted again by the flow control valve 7 below the conveying funnel 9 by the wind speed meter 17 and the concentration monitor 14, so as to accurately control the test variables.

[0042] This simulation device can be used to conduct erosion and wear tests, friction tests, and other similar tests.

[0043] (1) Erosion and wear test

[0044] By placing the specimen in this simulation device, the degree of erosion and wear can be accurately quantified during the study of the specimen undergoing particle erosion and wear.

[0045] Assume the specimen mass before the test is m0 (in g); the specimen mass after the test is m1 (in g); therefore, the weight loss after the test is Δm = m0 - m1 (in g).

[0046] Using the erosion rate δ (or wear rate) to represent the degree of erosion (wear), we can obtain:

[0047]

[0048] Where M s The feed rate of the simulation device is expressed in g / min; t is the erosion time of the specimen, expressed in min.

[0049] (2) Friction test

[0050] This experimental setup can also be used to conduct friction tests on moving pairs in particulate environments, providing a reference for the dynamic and reliability studies of related moving mechanisms. Taking a pair of specimens made of 25Cr2Ni4MA and 30CrMnMo materials as an example, the variation of the friction coefficient with wind speed and material conveying rate was studied. Multiple measurements were taken to obtain the friction coefficients of the pair under different wind speeds and material conveying rates. After fitting the results using post-processing software (MATLAB), it was found that the polynomial fitting method yielded the best fit compared to the experimental curves. The mathematical model obtained after polynomial fitting is as follows:

[0051] μ = 0.33 - 0.051V + 0.0068M s

[0052] Where μ is the coefficient of kinetic friction of the mating components; v is the wind speed of the simulated environment device, in m / s; M s The feed rate of this simulation device is expressed in g / min.

[0053] In addition, high-speed photography and other tools can be used in conjunction with this environmental simulation device to record the erosion process, friction dynamics, erosion results on the specimen surface, and particle adhesion.

Claims

1. A particle-containing environment simulation device, comprising a centrifugal fan, a test chamber, and a test bench disposed within the test chamber; characterized in that, The centrifugal fan is connected to the test chamber through a turbulent flow section; a material conveying funnel is provided on the air outlet of the centrifugal fan; The material conveying hopper is equipped with a flow control valve to control the opening and closing of the material conveying hopper and the flow rate, and is also equipped with a flow sensor to detect the real-time flow rate and transmit the detected data to a computer. The test bench is equipped with an attitude adjustment mechanism, which can adjust the distance between the test bench and the air outlet, as well as the windward angle of the test bench. The test chamber is equipped with an anemometer and a concentration monitor to detect the wind speed and particle concentration inside the test chamber and transmit the detected data to a computer. The computer is used to calculate the conveying rate based on the cross-sectional area of ​​the air outlet, the real-time detected wind speed and particle concentration, and to control the flow control valve below the conveying hopper and the speed controller of the centrifugal fan to meet the requirements of different experimental particle concentrations and the wind speed settings. The computer's control process satisfies: Calculations using relevant physical quantities in particulate environments: Conversion between feed rate and particulate concentration and feed rate M S The air outlet cross-sectional area A, wind speed V, and particulate concentration Q are related; the expression uses dimensionality, where the dimension refers to the category of the physical quantity, denoted by dim: dimQ=(dimV) α (dim. S ) β (dimA) γ (1) Where α, β, and γ are undetermined constants, and dimQ=ML -3 ,dimV=LT -1 ,dimM S =MT -1 ,dimA=L 2 (2) Substituting equation (2) into equation (1) yields... ML -3 =(LT -1 ) α (MT -1 ) β (L 2 ) γ =M β L 2γ+α T -α-β (3) Where the basic dimensions M, L, and T are the dimensions of mass, length, and time, respectively. Because dimensional analysis requires ensuring homogeneity of dimensions, we can obtain: α=1,2β+γ=-3,-α-β=0 (4) so α=1,β=-1,γ=-1 (5) so dimQ=(dimV) -1 (dim. S ) 1 (dimA) -1 (6) Right now Finally, the material feeding rate M can be obtained. S The formulas for converting between particle concentration Q and flow rate are based on the definition of flow rate in fluid mechanics, where the conveying rate is... Right now The simulation device can meet the particle concentration Q requirements of different tests according to the feeding rate.

2. The particulate environment simulation device according to claim 1, characterized in that, The test bench includes a test bench surface and a test bench base, and the attitude adjustment mechanism includes a lead screw, an intermediate plate, and a telescopic frame; One end of the intermediate plate is hinged to the support plate on the test bench base, and the other end is provided with a telescopic frame between the intermediate plate and the test bench base for adjusting the angle of the test bench; the intermediate plate is provided with multiple screws for adjusting the height of the test bench surface located on the intermediate plate.

3. The particulate environment simulation device according to claim 1, characterized in that, The test chamber is also equipped with a recovery section for recovering particulate matter.

4. The particulate environment simulation device according to claim 1, characterized in that, The test chamber is made of transparent material.

5. The particulate environment simulation device according to claim 1, characterized in that, For erosion and wear testing: The specimen is placed in the simulation device, and the degree of erosion is represented by the erosion rate δ, which is then obtained as the erosion rate δ: Where Δm is the weight loss of the specimen after the test; M s t represents the feed rate of the simulation device; t represents the erosion time of the specimen.

6. The particulate environment simulation device according to claim 1, characterized in that, For friction testing: The mating components are placed in this simulation device to study the change of the friction coefficient with wind speed and conveying rate. The result can be obtained through polynomial fitting. μ=0.33-0.051v+0.0068M s Where μ is the coefficient of kinetic friction of the paired components; v is the wind speed of the simulated environment device; and M is the dynamic friction coefficient of the paired components. s The feed rate of this simulation device is denoted as .

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